6. Jamal Lewis (2,066 Yards, 14 Touchdowns)

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Jamal Lewis may have had the second-most rushing yards in a single season in NFL history, but overall his season wasn't as impressive as the others. His 5.3 yards per carry were the second-worst average of the 2,000-yard rushers.

His receiving yards were also not that impressive, as he only had 205 receiving yards. Touchdowns were also just middle of the pack at 14.

He was very important to his team, though. The Ravens defense was very good in 2003, but on offensive he was really the only threat. The two quarterbacks, Anthony Wright and Kyle Boller, combined for 2,459 yards 16 touchdowns and 17 interceptions. Without Lewis it is unlikely that the Ravens would have made the playoffs and won the division.

Still for a 2,000-yard rusher, his stats just didn't jump out in any way, and thus he will be ranked sixth.

5. Barry Sanders (2,053 Yards, 11 Touchdowns)

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Barry Sanders was probably the greatest pure runner in the history of the NFL, unfortunately though, his 1997 season was only good enough for fifth on this list.

Barry had very good numbers all around and his 2,053 yards are third all-time, but he only had 11 touchdowns. However, unlike Jamal Lewis, Sanders had a very good season receiving. He had 305 receiving yards and three touchdowns.

Barry was probably the most important player on his team. The Lions did have a solid quarterback, Scott Mitchell, and good receivers, Herman Moore and Johnie Morton, but Barry made this offense go. Without Barry the offense would not have been nearly as good, and there is no way they make the playoffs without him.

4. Eric Dickerson (2,105 Yards, 14 Touchdowns)

Eric Dickerson is the record holder for the most rushing yards in a season, yet his 2,000-yard season is only fourth on this list. Why?

Well, despite rushing for 2,105 yards, he only had 14 touchdowns, middle of the pack for players on this list. He also only had 139 receiving yards and failed to score through the air.

Still he is the single-season rushing record holder and that must be given some weight, but considering how close everyone on this list is as far as rush yardage, it there is only a 102-yard difference between the highest and lowest totals, that really doesn't make him the runaway leader.

On the bright side, he was very important to his team. Of all the players on this list so far, his team may have been the worst. His quarterback, Jeff Kemp, only threw 13 touchdowns, and no receiver gained 1,000 yards. The defense was pretty good, but not one player from that unit made the Pro Bowl the year Dickerson rushed for 2,000.

3. Terrell Davis (2,008 Yards, 21 Touchdowns)

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Terrell Davis gets the number three spot on this list for one reason: He was thee most prolific scorer among the 2,000-yard club. In 1998, the year he had 2,000, Davis rushed for 21 touchdowns and added two through the air. That's 23 touchdowns.

To put it in perspective, the second-best touchdown total in the 2,000-yard club is 16, by Chris Johnson.

He was also very instrumental in helping John Elway win two titles. Davis provided a strong run game that opened up passing lanes for the great Elway to throw into. Without him the offense just wouldn't have been the same.

2. Chris Johnson (2,006 Rushing Yards, 14 Touchdowns)

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Chris Johnson's 2009 season was one of the most amazing ever. He gained 2,006 yards on the ground, 503 in the air, and scored 16 total touchdowns. With his combined rushing and recieving yards he also broke Marshall Faulk's single-season yards from scrimmage record.

By gaining the most total yards and second most scores in the 2,000-yard club Johnson assures himself a place at number two.

1. O.J. Simpson (2,003 Yards, 12 Touchdowns)

Looking just at the stats, O.J. seems to have the weakest season among the 2,000-yard club. He was last in rushing yards, receiving yards and total touchdowns. So why is he number one?

Because O.J. Simpson rushed for his 2,000 in only 14 games, the length of the season in 1973. No one has ever made it to 2,000 yards in 14 games except O.J. The next best was Eric Dickerson getting to 2,000 in 15 games.

To get to 2,000 yards in 14 games, O.J. had to average 143.1 yards a game, which is the all-time record. The second best to that is Jim Brown's 133.1 yards per game—10 yards less.

O.J. dominated on the ground that season like no one ever had before, and probably ever will again. If O.J. had played 16 games like everyone else in the 2,000-yard club and kept up his pace, he would have had 2,289 yards—184 more yards than Dickerson.

So even though he has the least yards, O.J. Simpson gets number one because he had the best season rushing ever.